This is an archival study. Recently developed sequential analytic techniques will be applied to systematic observational data collected in the 1970s on the hunter-gather |Kung living in northwestern Botswana. The purpose is, first, to describe the developmental course of |Kung San infants' communicative acts such as crying, vocalizing, smiling, and verbalizing and to describe the social context of these acts. This work will result in a detailed picture of how |Kung infants' social partners respond to the infants' first communicative attempts (e.g., by assisting, amusing, encouraging, discouraging, vocalizing, or offering objects). For comparison, responses to infants' object manipulations and motoric acts will also be examined. Second, we will use these descriptions to test the generality of current ideas suggested by Vygotsky, Bruner, and others concerning the importance of object sharing for communication development. Because the |Kung's childrearing contrast so markedly with Western practices, this work should deepen our understanding about specific relationships between particular infant accomplishments and adult tuition.